1. Field of the Invention
The present invention is related to tools used in masonry work. In particular, the present invention is related to tools for use in temporarily closing openings in masonry while the masonry is grouted, or filled with like material.
2. Background of the Invention
The general art of masonry work is, of course, an extremely old art. In essence, masonry work involves binding together "masonry units" such as bricks, blocks, and stone. These masonry units are held together with some type of mortar.
In modern construction, the mortar is made up of several separate components, which components may be varied depending on the desired characteristics of the mortar. One of the primary elements of mortar is a cement component which contributes strength and durability to the mortar mix. In addition, lime may be added to the mortar to add workability, the ability to retain water, and elasticity. Both cement and lime components contribute to the bond strength of the mortar mix.
In addition, sand may be added which acts as a filler and which also contributes to the strength of the mix. Sand enables the unset mortar mix to retain its shape and thickness under the pressure of several masonry units. A final component of mortar is generally water which acts as a mixing agent and gives workability to the resulting mortar mix.
As mentioned above, the various components of mortar may be varied in order to provide various types of properties. The desired properties will, of course, depend on the expected use of the mortar mix. Mortar mixes may vary from extremely thick mortars used to hold together stone and block, to very thin mortars, such a grout, which are used to fill voids within the masonry structure.
Grout is generally defined as a thin, or wet mortar. This thin, wet mortar may be added to the interior of a masonry structure to fill the voids within the interior. In addition, it may be added to other portions of the structure to fill voids or to provide additional strength at desired locations.
Grout is a particularly important structural element when using concrete blocks. Conventional concrete blocks include hollow voids within the blocks. When constructing large structures using this type of block, it is necessary to provide additional reinforcement to the interior of the structure. As a result, it is conventional in the art to add structural steel rod which runs through the interior of the hollow concrete blocks.
Increasingly, rigid construction codes also now typically require that the interior of concrete block construction be supplemented with a grout material. Thus, it is typical to fill voids within concrete blocks with a thin, wet grout material.
In order to confirm that the grout material has flowed through the entire masonry wall, construction codes now typically require that "cleanout holes" be provided at the base of each of the channels through which the grout flows. Such grout channels are often referred to as "pours." A typical state building code provides that "cleanout openings shall be provided at the bottom of each pour of grout. Any overhanging mortar or other debris shall be removed from the insides of cell walls. The foundation or other horizontal construction joints shall be cleaned of all loose material and mortar droppings before each pour. The cleanout shall be sealed before grouting." See Utah State Building Code .sctn. 2-2415(c).
The purpose of cleanout holes is readily apparent. These openings allow an inspector to confirm that a high-rise masonry wall has been properly grouted and to observe that grout has flowed all the way to the base of each channel or pour within the wall. In addition, such cleanout holes are required in order to remove certain debris, such as mortar droppings and the like, which may have fallen through the openings in the interior of a concrete block or similar building material and which may obstruct the pouring of the grout.
The problem which is encountered in providing such cleanout holes, however, is with respect to closing the cleanout hole during the pouring of grouting. It will be appreciated that, with a "high lift" masonry wall, the fluid pressure of grout against the cleanout hole opening may be extremely large. Thus, it has been a problem to provide adequate means of blocking the cleanout hole while it is being filled with grout.
The present practice in the art is simply to fill the cleanout hole with some type of makeshift cover. The cover may include an appropriately shaped piece of plywood which is wedged within the hole. The cover then may be braced by an external brace, such as a wood structure wedged against the wall. The existing methods, however, do not rely on the masonry wall itself in order to brace the cover in place during grouting.
In using such makeshift coverings, additional problems are encountered. In particular, building codes and codes of practice require that the covering of the cleanout hole be maintained securely in place as the grouting is added to the wall. Using the makeshift externally anchored coverings described above, however, it is often found that the strain of fluid pressure on the covering will force it out of place, resulting in uneven grouting in the area of the cleanout hole, or leakage of grout out of the opening.
In order to correct the problem of slippage of the cover, it is necessary to expend a large amount of labor in properly setting the cover and bracing it. As a result, the grouting process becomes more and more labor intensive and thus extremely expensive. At the same time, the covers used are not particularly effective and may, indeed, result in defective grouting.
The extreme fluid pressure encountered during grouting is anticipated in the applicable standards set by the "National Concrete Masonry Association." That association states that mortar should be permitted to cure for 24 hours before grouting in order to prevent "blowout" of the mortar joints by the high grouting pressure. In addition, when filling a cavity space between two wythes of masonry, a drying period of not less than 3 days is recommended in order to prevent blowouts. Thus, it can be seen that the pressures encountered in grouting are sufficient to damage the masonry wall itself unless the joints are adequately dried. Obviously, the makeshift covers conventionally used in the art suffer severe problems, particularly since they cannot be anchored directly into the wall itself.
Once the grouting is complete, the cover of the cleanout hole is removed to allow inspection of the grouting fill. If the grouting fill is found to be adequate, the cleanout hole may be covered with a block facing which has a similar appearance to the block used in the remainder of the structure.
In view of the discussion above, it will be appreciated that what is needed in the art are adequate methods and apparatus for filling cleanout holes during grouting. In particular, it would be a significant advancement in the art to provide such methods and apparatus which are not labor intensive in their use. It would also be an advancement in the art to provide such methods and apparatus which were able to withstand the high fluid pressure of grout as it is being filled within a masonry structure by being anchored to the masonry wall itself.
It would be an additional advancement in the art to provide such an apparatus which was easily inserted and removed within a cleanout hole in a masonry structure. It would be a further advancement in the art to provide such an apparatus which was repeatedly usable such that the overall cost of using the apparatus was low. Furthermore, it would be a significant advancement in the art if such methods and apparatus could be developed which were simple and inexpensive to use such that the cost of the overall masonry structure could be reduced. Such methods and apparatus are disclosed and claimed herein.